Napkin holder



FIG. 1 is a perspective view of a napkin holder showing my new design;

FIG. 2 is a front view thereof, a rear view being identical;

FIG. 3 is a left side view thereof, a right side view being identical;

FIG. 4 is a top view thereof; and,

FIG. 5 is a bottom view thereof.

The broken lines in the figures illustrate portions of the design that form no part of the claimed design. 

CLAIM The ornamental design for a napkin holder, as shown and described. 